diff options
Diffstat (limited to 'net/vmw_vsock/hyperv_transport.c')
| -rw-r--r-- | net/vmw_vsock/hyperv_transport.c | 93 |
1 files changed, 70 insertions, 23 deletions
diff --git a/net/vmw_vsock/hyperv_transport.c b/net/vmw_vsock/hyperv_transport.c index 62dcdf082349..f2084e3f7aa4 100644 --- a/net/vmw_vsock/hyperv_transport.c +++ b/net/vmw_vsock/hyperv_transport.c @@ -14,14 +14,14 @@ #include <net/sock.h> #include <net/af_vsock.h> -/* The host side's design of the feature requires 6 exact 4KB pages for - * recv/send rings respectively -- this is suboptimal considering memory - * consumption, however unluckily we have to live with it, before the - * host comes up with a better design in the future. +/* Older (VMBUS version 'VERSION_WIN10' or before) Windows hosts have some + * stricter requirements on the hv_sock ring buffer size of six 4K pages. Newer + * hosts don't have this limitation; but, keep the defaults the same for compat. */ #define PAGE_SIZE_4K 4096 #define RINGBUFFER_HVS_RCV_SIZE (PAGE_SIZE_4K * 6) #define RINGBUFFER_HVS_SND_SIZE (PAGE_SIZE_4K * 6) +#define RINGBUFFER_HVS_MAX_SIZE (PAGE_SIZE_4K * 64) /* The MTU is 16KB per the host side's design */ #define HVS_MTU_SIZE (1024 * 16) @@ -46,8 +46,9 @@ struct hvs_recv_buf { }; /* We can send up to HVS_MTU_SIZE bytes of payload to the host, but let's use - * a small size, i.e. HVS_SEND_BUF_SIZE, to minimize the dynamically-allocated - * buffer, because tests show there is no significant performance difference. + * a smaller size, i.e. HVS_SEND_BUF_SIZE, to maximize concurrency between the + * guest and the host processing as one VMBUS packet is the smallest processing + * unit. * * Note: the buffer can be eliminated in the future when we add new VMBus * ringbuffer APIs that allow us to directly copy data from userspace buffer @@ -321,8 +322,11 @@ static void hvs_open_connection(struct vmbus_channel *chan) struct sockaddr_vm addr; struct sock *sk, *new = NULL; struct vsock_sock *vnew = NULL; - struct hvsock *hvs, *hvs_new = NULL; + struct hvsock *hvs = NULL; + struct hvsock *hvs_new = NULL; + int rcvbuf; int ret; + int sndbuf; if_type = &chan->offermsg.offer.if_type; if_instance = &chan->offermsg.offer.if_instance; @@ -364,9 +368,34 @@ static void hvs_open_connection(struct vmbus_channel *chan) } set_channel_read_mode(chan, HV_CALL_DIRECT); - ret = vmbus_open(chan, RINGBUFFER_HVS_SND_SIZE, - RINGBUFFER_HVS_RCV_SIZE, NULL, 0, - hvs_channel_cb, conn_from_host ? new : sk); + + /* Use the socket buffer sizes as hints for the VMBUS ring size. For + * server side sockets, 'sk' is the parent socket and thus, this will + * allow the child sockets to inherit the size from the parent. Keep + * the mins to the default value and align to page size as per VMBUS + * requirements. + * For the max, the socket core library will limit the socket buffer + * size that can be set by the user, but, since currently, the hv_sock + * VMBUS ring buffer is physically contiguous allocation, restrict it + * further. + * Older versions of hv_sock host side code cannot handle bigger VMBUS + * ring buffer size. Use the version number to limit the change to newer + * versions. + */ + if (vmbus_proto_version < VERSION_WIN10_V5) { + sndbuf = RINGBUFFER_HVS_SND_SIZE; + rcvbuf = RINGBUFFER_HVS_RCV_SIZE; + } else { + sndbuf = max_t(int, sk->sk_sndbuf, RINGBUFFER_HVS_SND_SIZE); + sndbuf = min_t(int, sndbuf, RINGBUFFER_HVS_MAX_SIZE); + sndbuf = ALIGN(sndbuf, PAGE_SIZE); + rcvbuf = max_t(int, sk->sk_rcvbuf, RINGBUFFER_HVS_RCV_SIZE); + rcvbuf = min_t(int, rcvbuf, RINGBUFFER_HVS_MAX_SIZE); + rcvbuf = ALIGN(rcvbuf, PAGE_SIZE); + } + + ret = vmbus_open(chan, sndbuf, rcvbuf, NULL, 0, hvs_channel_cb, + conn_from_host ? new : sk); if (ret != 0) { if (conn_from_host) { hvs_new->chan = NULL; @@ -424,6 +453,7 @@ static u32 hvs_get_local_cid(void) static int hvs_sock_init(struct vsock_sock *vsk, struct vsock_sock *psk) { struct hvsock *hvs; + struct sock *sk = sk_vsock(vsk); hvs = kzalloc(sizeof(*hvs), GFP_KERNEL); if (!hvs) @@ -431,7 +461,8 @@ static int hvs_sock_init(struct vsock_sock *vsk, struct vsock_sock *psk) vsk->trans = hvs; hvs->vsk = vsk; - + sk->sk_sndbuf = RINGBUFFER_HVS_SND_SIZE; + sk->sk_rcvbuf = RINGBUFFER_HVS_RCV_SIZE; return 0; } @@ -627,7 +658,9 @@ static ssize_t hvs_stream_enqueue(struct vsock_sock *vsk, struct msghdr *msg, struct hvsock *hvs = vsk->trans; struct vmbus_channel *chan = hvs->chan; struct hvs_send_buf *send_buf; - ssize_t to_write, max_writable, ret; + ssize_t to_write, max_writable; + ssize_t ret = 0; + ssize_t bytes_written = 0; BUILD_BUG_ON(sizeof(*send_buf) != PAGE_SIZE_4K); @@ -635,20 +668,34 @@ static ssize_t hvs_stream_enqueue(struct vsock_sock *vsk, struct msghdr *msg, if (!send_buf) return -ENOMEM; - max_writable = hvs_channel_writable_bytes(chan); - to_write = min_t(ssize_t, len, max_writable); - to_write = min_t(ssize_t, to_write, HVS_SEND_BUF_SIZE); - - ret = memcpy_from_msg(send_buf->data, msg, to_write); - if (ret < 0) - goto out; + /* Reader(s) could be draining data from the channel as we write. + * Maximize bandwidth, by iterating until the channel is found to be + * full. + */ + while (len) { + max_writable = hvs_channel_writable_bytes(chan); + if (!max_writable) + break; + to_write = min_t(ssize_t, len, max_writable); + to_write = min_t(ssize_t, to_write, HVS_SEND_BUF_SIZE); + /* memcpy_from_msg is safe for loop as it advances the offsets + * within the message iterator. + */ + ret = memcpy_from_msg(send_buf->data, msg, to_write); + if (ret < 0) + goto out; - ret = hvs_send_data(hvs->chan, send_buf, to_write); - if (ret < 0) - goto out; + ret = hvs_send_data(hvs->chan, send_buf, to_write); + if (ret < 0) + goto out; - ret = to_write; + bytes_written += to_write; + len -= to_write; + } out: + /* If any data has been sent, return that */ + if (bytes_written) + ret = bytes_written; kfree(send_buf); return ret; } |